Scan converter to monitor problem

[ssmrpopo]

OK I've got my scan converter hooked up to my monitor and the picture is great most of the time, but evary so often the screen will start to vertical roll slightly. First it starts slow then it will speed up then it will go away for a few seconds. It doesn't really do it in any definate time patern and you can't really tell when there is action on the screen. Adjusting the vertical hold for the monitor does not help either. Does this sound like a wiring problem, a monitor problem, or an issue with the converter? The converter is a Truevision Vidi/o box with composite and s-video inputs and I have the same problem for both inputs. Any suggestions would be appreciated. Thanks!

[generousben]

throw it in the bin.

[ssmrpopo]

The RGB output of the scan conveerter are only .71vp-p could they be too weak and I'm cranking up the levels on the monitor too high? I don't want to give up yet!

[SNAAAKE]

I am having similer problem too..its very good looking and playable too except when you are in a white screen..you can see the blinking/rolling.

However,my extron emotia scan converter works perfectly with tv but with RGB..its acting kinda funny.

anyone?know?anything?

any help would be great.
also,it happens more when i am running dreamcast through VGA box(640x480).but less in windows.